10
696 episodes 12% had none of the characteristic CSF findings (CSF glucose 2.2g, WCC >2000) Well recognised that meningococcal sepsis with early meningitis may have low CSF WCC

11
Diagnosis Meningococcal septicaemia and meningitis

12

13
Role of PCR in diagnosis of invasive meningococcal disease NICE: all patients < 16 with suspected meningococcal disease get: –blood culture –PCR on EDTA blood –CSF culture with CSF PCR if culture is negative Data from MRU across all ages: 57% were confirmed by PCR only, 22.5% by culture only, 20.4% by both tests

14

15
Send blood cultures early Send an early EDTA blood for PCR Request PCR on CSF Early samples are more likely to be positive PCR results may still be positive after antibiotic administration

16
Case 2 42F married secondary school teacher Lives with husband and 2 adult children Normally fit and well BIBA to A&E 2-3 day history flu like symptoms Back ache, severe headache, photophobia Mild dysuria

20
No recent travel No contacts unwell No known TB contacts, never lived abroad No immunosuppressive Rx No previous episodes of meningitis Thinks had all childhood vaccinations, unsure of details Married for 10 years No new sexual partners No recent antibiotics Denies exposure to rodents or ticks ROS: mild dysuria/perineal discomfort recently, no response to canestan

32
HSV meningitis is often a complication of genital herpes especially HSV-2 36% of women and 13% of men with primary genital HSV-2 infection had aseptic meningitis Frequently occurs in absence of genital lesions / history of genital lesions May occur during reactivation

33
May be complicated by radiculitis, myelitis, recurrent meningitis (with or without genital symptoms) Role of antivirals in HSV-2 meningitis: –Indicated for primary genital herpes infection –Variability in practice for HSV-2 meningitis –Prophylaxis: sometimes given. RCT of valaciclovir 500mg bd Asymptomatic intermittent shedding and transmission years into a monogamous relationship

54
Repeat LP for large volume CSF Day 2 of admission, 6mls CSF collected and sent same day to TB ref lab for TB PCR Result within 24 hours: PCR positive indicating the presence of Mycobacterium tuberculosis complex. Genotype is that seen in rifampicin susceptible isolates.

55
Continued TB Rx and steroids Other antimicrobials stopped

56
TBM All methods of TB detection in CSF are heavily dependent on sample volume Sensitivity of smear and culture fall off rapidly after Rx started PCR: –~30% sensitivity on 0.5 mls CSF –Up to 70% sensitivity on large volume e.g. 6mls –Negative doesn’t exclude but a positive result very useful